Unable to Move Contacts

I have bunch of contacts added in Windows Messenger which I'm managing them
and putting them into groups. I have some of them already into their desired
groups I created.

The only problem now I cannot move anymore contacts into any more groups. I
thought it might have been a glitch so I decided to signout and sign back in
my .Net Passport account but that didn't solve it. When I right-click on any
of my contacts, the menu appears with different options but the "Move
contact to" option is greyed out.

Any suggestions?


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